cho a = 1/1.21 + 1/2.22+...+1/80.100 b= 1/1.81 + 1/2.82+...+1/20.100 tính a/b
Cho A=1/1.21+1/1.22+1/3.23+...+1/80.100
B=1/1.81+1/2.82+1/3.83+...+1/20.100
Tính A/B
tính a/b biết a=1/1.21 + 1/2.22 + 1/3.23 + ... +1/80.100; b=1/1.81 + 1/2.82 + 1/3.82 + ... + 1/20.100
Câu 24 : Cho A = 1.21 + 1/2.22 + 1/3.23 + ... + 1/80.100 ; B = 1/1.81 + 1/2.82 + 1/3.83 + ... + 1/20.100 . Tính A/B
Cho \(A=\dfrac{1}{1.21}+\dfrac{1}{2.22}+\dfrac{1}{3.23}+...+\dfrac{1}{80.100}\);
\(B=\dfrac{1}{1.81}+\dfrac{1}{2.82}+\dfrac{1}{3.83}+...+\dfrac{1}{20.100}\).
Tính \(\dfrac{A}{B}\).
Cho \(A=\frac{1}{1.21}+\frac{1}{2.22}+\frac{1}{3.23}+......+\frac{1}{80.100}\)
\(B=\frac{1}{1.81}+\frac{1}{2.82}+\frac{1}{3.83}+....+\frac{1}{20.100}\). Tính \(\frac{A}{B}\)
1/18 +1/54 +1/108+.....+1/990
1/20+1/30+1/40+....+1/990
F=1/18+1/54+1/108+...+1/990 =?
1/20 + 1/30 +1/42 +1/56 + .. + 1/990